Jim Hendler wrote:
> >- default values for attributes
> > Not even in Full OWL
>
> I think the term "default" is used differently here - in UML the
> defaults can be, essentially, monotonic, in the sense that it is a
> default that a female mammal lactates to feed its young (this is
> definitional, no exceptions in the natural world) -- using the
> notion of default as "All of them have this value so it doesn't have
> to be specified on each"
I don't think that this is the UML semantics for default value. Well,
actually most UML books do not do a good job at defining it. The User
Guide of the three amigo's [1] gives the example of a class "Wall" with
an attribute "isLoadBearing" which has a default value "false" (clearly
not true for every wall). No further explanation is given of what may
constitute a default value. The OMG UML document [2] uses the term
"initial" instead of "default" (which seems to stem from a programming
view).
Guus
[1] Booch, Rumbaugh & Jaconson. The Unified Modelling Language User
Guide. Addison Wesley, 1999.
[2] http://www.rational.com/media/uml/post.pdf
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